Communications is the transmission of intelligence between two or more points. The science and technology of communication deals with the manner in which information is collected from an originating source, transformed into electric currents or fields, transmitted over electrical networks or space to another point, and reconverted into a form suitable for interpretation by a receiver.
Typically, communications systems consists of cascaded networks, each network designed to carry out some operation on the energy conveying the information. Antennas are often the networks serving to transfer the signal energy from circuits to space and, conversely, from space to circuits. The signal energy is in the form of beams i.e. a plurality of straight lines in which each straight line represents a beam. The beams are a collimated or approximately unidirectional flow of electromagnetic radiation. The distribution of the radiated energy varies with the direction in space and with the distance from the antenna. This gives rise to the directive properties of the antenna.
Satellite communications antennas have been developed to provide precisely tailored beams to cover multiple designated coverage areas on the earth without wasting antenna radiated power on regions where there are no users of interest. The prior art utilized multibeam antennas or phased arrays to provide precisely tailored beams.
Space bound antennas were individually designed and assembled for a particular satellite. Each satellite was usually launched for a specific purpose. Each element of the many elements of the antenna had to be individually fabricated and assembled. Thus, the antenna was very expensive to fabricate and assemble. The satellite antenna industry has not heretofore provided an antenna that did not use completely different antenna components, notwithstanding that packaging engenders efficiency in manufacturing, and also importantly provides the necessary flexibility to design antennas that meet different satellite needs.
One of the disadvantages of the prior art was that multibeam antennas and phased arrays were large and heavy.
An additional disadvantage of the prior art was that multibeam antennas and phase arrays were difficult and expensive to implement on a recurring basis.